Metabolic modulation: Pneumocystis phosphoglucomutase is a target influencing host recognition

Area of Science:

• Biochemistry
• Mycology
• Molecular Biology

Background:

• Mannoproteins on the fungal surface are crucial for host-pathogen interactions.
• The phosphoglucomutase (PGM) enzyme's role in Pneumocystis mannoprotein synthesis is not well understood.

Purpose of the Study:

• To investigate the function of phosphoglucomutase (PGM) in Pneumocystis spp.
• To explore the role of PGM in fungal cell wall mannoprotein formation.
• To assess the potential of PGM as a therapeutic target.

Main Methods:

• Expressing the Pneumocystis murina Pmpgm2 gene in a Saccharomyces cerevisiae pgm2Δ mutant strain.
• Assessing mannose receptor (MR) binding and macrophage interaction.
• Utilizing Gas Chromatography-Mass Spectroscopy (GC-MS) to quantify mannose content.

Main Results:

• Complementation of the S. cerevisiae pgm2Δ strain with Pmpgm2 restored MR and macrophage binding to wild-type levels.
• GC-MS analysis revealed reduced mannose content in the pgm2Δ yeast strain.
• The study highlights PGM's role in dolichol glucosyl phosphate biosynthesis for cell wall integrity.

Conclusions:

• Fungal PGM is essential for proper mannoprotein formation and cell wall biosynthesis.
• Conserved targetable cysteine residues in PGM across fungal pathogens suggest potential for broad-spectrum therapeutic strategies.
• PGM inhibition presents a promising avenue for developing new antifungal treatments.